Generated by https://github.com/apache/kafka/pull/970 on 2/25/2016

kafka_protocol.html

<h4>Api Keys</h4><p>The following are the numeric codes that the ApiKey in the request can take for each of the above request types.</p><table class="data-table"><tbody>
<tr>
<th>Name</th>
<th>Key</th>
</tr>
<tr>
<td>Produce</td><td>0</td></tr>
<tr>
<td>Fetch</td><td>1</td></tr>
<tr>
<td>Offsets</td><td>2</td></tr>
<tr>
<td>Metadata</td><td>3</td></tr>
<tr>
<td>LeaderAndIsr</td><td>4</td></tr>
<tr>
<td>StopReplica</td><td>5</td></tr>
<tr>
<td>UpdateMetadata</td><td>6</td></tr>
<tr>
<td>ControlledShutdown</td><td>7</td></tr>
<tr>
<td>OffsetCommit</td><td>8</td></tr>
<tr>
<td>OffsetFetch</td><td>9</td></tr>
<tr>
<td>GroupCoordinator</td><td>10</td></tr>
<tr>
<td>JoinGroup</td><td>11</td></tr>
<tr>
<td>Heartbeat</td><td>12</td></tr>
<tr>
<td>LeaveGroup</td><td>13</td></tr>
<tr>
<td>SyncGroup</td><td>14</td></tr>
<tr>
<td>DescribeGroups</td><td>15</td></tr>
<tr>
<td>ListGroups</td><td>16</td></tr>
</table>
<h4>Error Codes</h4><p>We use numeric codes to indicate what problem occurred on the server. These can be translated by the client into exceptions or whatever the appropriate error handling mechanism in the client language. Here is a table of the error codes currently in use:</p><table class="data-table"><tbody>
<tr>
<th>Error</th>
<th>Code</th>
<th>Retriable</th>
<th>Description</th>
</tr>
<tr>
<td>UNKNOWN</td><td>-1</td><td>False</td><td>The server experienced an unexpected error when processing the request</td></tr>
<tr>
<td>NONE</td><td>0</td><td>False</td><td></td></tr>
<tr>
<td>OFFSET_OUT_OF_RANGE</td><td>1</td><td>False</td><td>The requested offset is not within the range of offsets maintained by the server.</td></tr>
<tr>
<td>CORRUPT_MESSAGE</td><td>2</td><td>True</td><td>This message has failed its CRC checksum, exceeds the valid size, or is otherwise corrupt.</td></tr>
<tr>
<td>UNKNOWN_TOPIC_OR_PARTITION</td><td>3</td><td>True</td><td>This server does not host this topic-partition.</td></tr>
<tr>
<td>INVALID_FETCH_SIZE</td><td>4</td><td>False</td><td>The requested fetch size is invalid.</td></tr>
<tr>
<td>LEADER_NOT_AVAILABLE</td><td>5</td><td>True</td><td>There is no leader for this topic-partition as we are in the middle of a leadership election.</td></tr>
<tr>
<td>NOT_LEADER_FOR_PARTITION</td><td>6</td><td>True</td><td>This server is not the leader for that topic-partition.</td></tr>
<tr>
<td>REQUEST_TIMED_OUT</td><td>7</td><td>True</td><td>The request timed out.</td></tr>
<tr>
<td>BROKER_NOT_AVAILABLE</td><td>8</td><td>False</td><td>The broker is not available.</td></tr>
<tr>
<td>REPLICA_NOT_AVAILABLE</td><td>9</td><td>False</td><td>The replica is not available for the requested topic-partition</td></tr>
<tr>
<td>MESSAGE_TOO_LARGE</td><td>10</td><td>False</td><td>The request included a message larger than the max message size the server will accept.</td></tr>
<tr>
<td>STALE_CONTROLLER_EPOCH</td><td>11</td><td>False</td><td>The controller moved to another broker.</td></tr>
<tr>
<td>OFFSET_METADATA_TOO_LARGE</td><td>12</td><td>False</td><td>The metadata field of the offset request was too large.</td></tr>
<tr>
<td>NETWORK_EXCEPTION</td><td>13</td><td>True</td><td>The server disconnected before a response was received.</td></tr>
<tr>
<td>GROUP_LOAD_IN_PROGRESS</td><td>14</td><td>True</td><td>The coordinator is loading and hence can't process requests for this group.</td></tr>
<tr>
<td>GROUP_COORDINATOR_NOT_AVAILABLE</td><td>15</td><td>True</td><td>The group coordinator is not available.</td></tr>
<tr>
<td>NOT_COORDINATOR_FOR_GROUP</td><td>16</td><td>True</td><td>This is not the correct coordinator for this group.</td></tr>
<tr>
<td>INVALID_TOPIC_EXCEPTION</td><td>17</td><td>False</td><td>The request attempted to perform an operation on an invalid topic.</td></tr>
<tr>
<td>RECORD_LIST_TOO_LARGE</td><td>18</td><td>False</td><td>The request included message batch larger than the configured segment size on the server.</td></tr>
<tr>
<td>NOT_ENOUGH_REPLICAS</td><td>19</td><td>True</td><td>Messages are rejected since there are fewer in-sync replicas than required.</td></tr>
<tr>
<td>NOT_ENOUGH_REPLICAS_AFTER_APPEND</td><td>20</td><td>True</td><td>Messages are written to the log, but to fewer in-sync replicas than required.</td></tr>
<tr>
<td>INVALID_REQUIRED_ACKS</td><td>21</td><td>False</td><td>Produce request specified an invalid value for required acks.</td></tr>
<tr>
<td>ILLEGAL_GENERATION</td><td>22</td><td>False</td><td>Specified group generation id is not valid.</td></tr>
<tr>
<td>INCONSISTENT_GROUP_PROTOCOL</td><td>23</td><td>False</td><td>The group member's supported protocols are incompatible with those of existing members.</td></tr>
<tr>
<td>INVALID_GROUP_ID</td><td>24</td><td>False</td><td>The configured groupId is invalid</td></tr>
<tr>
<td>UNKNOWN_MEMBER_ID</td><td>25</td><td>False</td><td>The coordinator is not aware of this member.</td></tr>
<tr>
<td>INVALID_SESSION_TIMEOUT</td><td>26</td><td>False</td><td>The session timeout is not within an acceptable range.</td></tr>
<tr>
<td>REBALANCE_IN_PROGRESS</td><td>27</td><td>False</td><td>The group is rebalancing, so a rejoin is needed.</td></tr>
<tr>
<td>INVALID_COMMIT_OFFSET_SIZE</td><td>28</td><td>False</td><td>The committing offset data size is not valid</td></tr>
<tr>
<td>TOPIC_AUTHORIZATION_FAILED</td><td>29</td><td>False</td><td>Not authorized to access topics: [Topic authorization failed.]</td></tr>
<tr>
<td>GROUP_AUTHORIZATION_FAILED</td><td>30</td><td>False</td><td>Not authorized to access group: Group authorization failed.</td></tr>
<tr>
<td>CLUSTER_AUTHORIZATION_FAILED</td><td>31</td><td>False</td><td>Cluster authorization failed.</td></tr>
<tr>
<td>INVALID_TIMESTAMP</td><td>32</td><td>False</td><td>The timestamp of the message is out of acceptable range.</td></tr>
</table>
<h4>Headers:</h4><pre>Request Header => api_key api_version correlation_id client_id 
  api_key => INT16
  api_version => INT16
  correlation_id => INT32
  client_id => NULLABLE_STRING
</pre>
<pre>Response Header => correlation_id 
  correlation_id => INT32
</pre>
<h4>Produce API (Key: 0):</h4>

<b>Requests:</b><br>
<p><pre>Produce Request (Version: 0) => acks timeout [topic_data] 
  topic_data => topic [data] 
    data => partition record_set 
      partition => INT32
      record_set => BYTES
    topic => STRING
  acks => INT16
  timeout => INT32
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>acks</td><td>The number of nodes that should replicate the produce before returning. -1 indicates the full ISR.</td></tr>
<tr>
<td>timeout</td><td>The time to await a response in ms.</td></tr>
<tr>
<td>topic_data</td><td></td></tr>
<tr>
<td>topic</td><td></td></tr>
<tr>
<td>data</td><td></td></tr>
<tr>
<td>partition</td><td></td></tr>
<tr>
<td>record_set</td><td></td></tr>
</table>
</p>
<p><pre>Produce Request (Version: 1) => acks timeout [topic_data] 
  topic_data => topic [data] 
    data => partition record_set 
      partition => INT32
      record_set => BYTES
    topic => STRING
  acks => INT16
  timeout => INT32
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>acks</td><td>The number of nodes that should replicate the produce before returning. -1 indicates the full ISR.</td></tr>
<tr>
<td>timeout</td><td>The time to await a response in ms.</td></tr>
<tr>
<td>topic_data</td><td></td></tr>
<tr>
<td>topic</td><td></td></tr>
<tr>
<td>data</td><td></td></tr>
<tr>
<td>partition</td><td></td></tr>
<tr>
<td>record_set</td><td></td></tr>
</table>
</p>
<p><pre>Produce Request (Version: 2) => acks timeout [topic_data] 
  topic_data => topic [data] 
    data => partition record_set 
      partition => INT32
      record_set => BYTES
    topic => STRING
  acks => INT16
  timeout => INT32
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>acks</td><td>The number of nodes that should replicate the produce before returning. -1 indicates the full ISR.</td></tr>
<tr>
<td>timeout</td><td>The time to await a response in ms.</td></tr>
<tr>
<td>topic_data</td><td></td></tr>
<tr>
<td>topic</td><td></td></tr>
<tr>
<td>data</td><td></td></tr>
<tr>
<td>partition</td><td></td></tr>
<tr>
<td>record_set</td><td></td></tr>
</table>
</p>
<b>Responses:</b><br>
<p><pre>Produce Response (Version: 0) => [responses] 
  responses => topic [partition_responses] 
    partition_responses => partition error_code base_offset 
      partition => INT32
      error_code => INT16
      base_offset => INT64
    topic => STRING
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>responses</td><td></td></tr>
<tr>
<td>topic</td><td></td></tr>
<tr>
<td>partition_responses</td><td></td></tr>
<tr>
<td>partition</td><td></td></tr>
<tr>
<td>error_code</td><td></td></tr>
<tr>
<td>base_offset</td><td></td></tr>
</table>
</p>
<p><pre>Produce Response (Version: 1) => [responses] throttle_time_ms 
  responses => topic [partition_responses] 
    partition_responses => partition error_code base_offset 
      partition => INT32
      error_code => INT16
      base_offset => INT64
    topic => STRING
  throttle_time_ms => INT32
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>responses</td><td></td></tr>
<tr>
<td>topic</td><td></td></tr>
<tr>
<td>partition_responses</td><td></td></tr>
<tr>
<td>partition</td><td></td></tr>
<tr>
<td>error_code</td><td></td></tr>
<tr>
<td>base_offset</td><td></td></tr>
<tr>
<td>throttle_time_ms</td><td>Duration in milliseconds for which the request was throttled due to quota violation. (Zero if the request did not violate any quota.)</td></tr>
</table>
</p>
<p><pre>Produce Response (Version: 2) => [responses] throttle_time_ms 
  responses => topic [partition_responses] 
    partition_responses => partition error_code base_offset timestamp 
      partition => INT32
      error_code => INT16
      base_offset => INT64
      timestamp => INT64
    topic => STRING
  throttle_time_ms => INT32
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>responses</td><td></td></tr>
<tr>
<td>topic</td><td></td></tr>
<tr>
<td>partition_responses</td><td></td></tr>
<tr>
<td>partition</td><td></td></tr>
<tr>
<td>error_code</td><td></td></tr>
<tr>
<td>base_offset</td><td></td></tr>
<tr>
<td>timestamp</td><td>The timestamp returned by broker after appending the messages. If CreateTime is used for the topic, the timestamp will be -1. If LogAppendTime is used for the topic, the timestamp will be the broker local time when the messages are appended.</td></tr>
<tr>
<td>throttle_time_ms</td><td>Duration in milliseconds for which the request was throttled due to quota violation. (Zero if the request did not violate any quota.)</td></tr>
</table>
</p>
<h4>Fetch API (Key: 1):</h4>

<b>Requests:</b><br>
<p><pre>Fetch Request (Version: 0) => replica_id max_wait_time min_bytes [topics] 
  topics => topic [partitions] 
    partitions => partition fetch_offset max_bytes 
      partition => INT32
      fetch_offset => INT64
      max_bytes => INT32
    topic => STRING
  replica_id => INT32
  max_wait_time => INT32
  min_bytes => INT32
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>replica_id</td><td>Broker id of the follower. For normal consumers, use -1.</td></tr>
<tr>
<td>max_wait_time</td><td>Maximum time in ms to wait for the response.</td></tr>
<tr>
<td>min_bytes</td><td>Minimum bytes to accumulate in the response.</td></tr>
<tr>
<td>topics</td><td>Topics to fetch.</td></tr>
<tr>
<td>topic</td><td>Topic to fetch.</td></tr>
<tr>
<td>partitions</td><td>Partitions to fetch.</td></tr>
<tr>
<td>partition</td><td>Topic partition id.</td></tr>
<tr>
<td>fetch_offset</td><td>Message offset.</td></tr>
<tr>
<td>max_bytes</td><td>Maximum bytes to fetch.</td></tr>
</table>
</p>
<p><pre>Fetch Request (Version: 1) => replica_id max_wait_time min_bytes [topics] 
  topics => topic [partitions] 
    partitions => partition fetch_offset max_bytes 
      partition => INT32
      fetch_offset => INT64
      max_bytes => INT32
    topic => STRING
  replica_id => INT32
  max_wait_time => INT32
  min_bytes => INT32
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>replica_id</td><td>Broker id of the follower. For normal consumers, use -1.</td></tr>
<tr>
<td>max_wait_time</td><td>Maximum time in ms to wait for the response.</td></tr>
<tr>
<td>min_bytes</td><td>Minimum bytes to accumulate in the response.</td></tr>
<tr>
<td>topics</td><td>Topics to fetch.</td></tr>
<tr>
<td>topic</td><td>Topic to fetch.</td></tr>
<tr>
<td>partitions</td><td>Partitions to fetch.</td></tr>
<tr>
<td>partition</td><td>Topic partition id.</td></tr>
<tr>
<td>fetch_offset</td><td>Message offset.</td></tr>
<tr>
<td>max_bytes</td><td>Maximum bytes to fetch.</td></tr>
</table>
</p>
<p><pre>Fetch Request (Version: 2) => replica_id max_wait_time min_bytes [topics] 
  topics => topic [partitions] 
    partitions => partition fetch_offset max_bytes 
      partition => INT32
      fetch_offset => INT64
      max_bytes => INT32
    topic => STRING
  replica_id => INT32
  max_wait_time => INT32
  min_bytes => INT32
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>replica_id</td><td>Broker id of the follower. For normal consumers, use -1.</td></tr>
<tr>
<td>max_wait_time</td><td>Maximum time in ms to wait for the response.</td></tr>
<tr>
<td>min_bytes</td><td>Minimum bytes to accumulate in the response.</td></tr>
<tr>
<td>topics</td><td>Topics to fetch.</td></tr>
<tr>
<td>topic</td><td>Topic to fetch.</td></tr>
<tr>
<td>partitions</td><td>Partitions to fetch.</td></tr>
<tr>
<td>partition</td><td>Topic partition id.</td></tr>
<tr>
<td>fetch_offset</td><td>Message offset.</td></tr>
<tr>
<td>max_bytes</td><td>Maximum bytes to fetch.</td></tr>
</table>
</p>
<b>Responses:</b><br>
<p><pre>Fetch Response (Version: 0) => [responses] 
  responses => topic [partition_responses] 
    partition_responses => partition error_code high_watermark record_set 
      partition => INT32
      error_code => INT16
      high_watermark => INT64
      record_set => BYTES
    topic => STRING
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>responses</td><td></td></tr>
<tr>
<td>topic</td><td></td></tr>
<tr>
<td>partition_responses</td><td></td></tr>
<tr>
<td>partition</td><td>Topic partition id.</td></tr>
<tr>
<td>error_code</td><td></td></tr>
<tr>
<td>high_watermark</td><td>Last committed offset.</td></tr>
<tr>
<td>record_set</td><td></td></tr>
</table>
</p>
<p><pre>Fetch Response (Version: 1) => throttle_time_ms [responses] 
  responses => topic [partition_responses] 
    partition_responses => partition error_code high_watermark record_set 
      partition => INT32
      error_code => INT16
      high_watermark => INT64
      record_set => BYTES
    topic => STRING
  throttle_time_ms => INT32
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>throttle_time_ms</td><td>Duration in milliseconds for which the request was throttled due to quota violation. (Zero if the request did not violate any quota.)</td></tr>
<tr>
<td>responses</td><td></td></tr>
<tr>
<td>topic</td><td></td></tr>
<tr>
<td>partition_responses</td><td></td></tr>
<tr>
<td>partition</td><td>Topic partition id.</td></tr>
<tr>
<td>error_code</td><td></td></tr>
<tr>
<td>high_watermark</td><td>Last committed offset.</td></tr>
<tr>
<td>record_set</td><td></td></tr>
</table>
</p>
<p><pre>Fetch Response (Version: 2) => throttle_time_ms [responses] 
  responses => topic [partition_responses] 
    partition_responses => partition error_code high_watermark record_set 
      partition => INT32
      error_code => INT16
      high_watermark => INT64
      record_set => BYTES
    topic => STRING
  throttle_time_ms => INT32
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>throttle_time_ms</td><td>Duration in milliseconds for which the request was throttled due to quota violation. (Zero if the request did not violate any quota.)</td></tr>
<tr>
<td>responses</td><td></td></tr>
<tr>
<td>topic</td><td></td></tr>
<tr>
<td>partition_responses</td><td></td></tr>
<tr>
<td>partition</td><td>Topic partition id.</td></tr>
<tr>
<td>error_code</td><td></td></tr>
<tr>
<td>high_watermark</td><td>Last committed offset.</td></tr>
<tr>
<td>record_set</td><td></td></tr>
</table>
</p>
<h4>Offsets API (Key: 2):</h4>

<b>Requests:</b><br>
<p><pre>Offsets Request (Version: 0) => replica_id [topics] 
  topics => topic [partitions] 
    partitions => partition timestamp max_num_offsets 
      partition => INT32
      timestamp => INT64
      max_num_offsets => INT32
    topic => STRING
  replica_id => INT32
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>replica_id</td><td>Broker id of the follower. For normal consumers, use -1.</td></tr>
<tr>
<td>topics</td><td>Topics to list offsets.</td></tr>
<tr>
<td>topic</td><td>Topic to list offset.</td></tr>
<tr>
<td>partitions</td><td>Partitions to list offset.</td></tr>
<tr>
<td>partition</td><td>Topic partition id.</td></tr>
<tr>
<td>timestamp</td><td>Timestamp.</td></tr>
<tr>
<td>max_num_offsets</td><td>Maximum offsets to return.</td></tr>
</table>
</p>
<b>Responses:</b><br>
<p><pre>Offsets Response (Version: 0) => [responses] 
  responses => topic [partition_responses] 
    partition_responses => partition error_code [offsets] 
      partition => INT32
      error_code => INT16
    topic => STRING
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>responses</td><td></td></tr>
<tr>
<td>topic</td><td></td></tr>
<tr>
<td>partition_responses</td><td></td></tr>
<tr>
<td>partition</td><td>Topic partition id.</td></tr>
<tr>
<td>error_code</td><td></td></tr>
<tr>
<td>offsets</td><td>A list of offsets.</td></tr>
</table>
</p>
<h4>Metadata API (Key: 3):</h4>

<b>Requests:</b><br>
<p><pre>Metadata Request (Version: 0) => [topics] 
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>topics</td><td>An array of topics to fetch metadata for. If no topics are specified fetch metadata for all topics.</td></tr>
</table>
</p>
<b>Responses:</b><br>
<p><pre>Metadata Response (Version: 0) => [brokers] [topic_metadata] 
  brokers => node_id host port 
    node_id => INT32
    host => STRING
    port => INT32
  topic_metadata => topic_error_code topic [partition_metadata] 
    partition_metadata => partition_error_code partition_id leader [replicas] [isr] 
      partition_error_code => INT16
      partition_id => INT32
      leader => INT32
    topic_error_code => INT16
    topic => STRING
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>brokers</td><td>Host and port information for all brokers.</td></tr>
<tr>
<td>node_id</td><td>The broker id.</td></tr>
<tr>
<td>host</td><td>The hostname of the broker.</td></tr>
<tr>
<td>port</td><td>The port on which the broker accepts requests.</td></tr>
<tr>
<td>topic_metadata</td><td></td></tr>
<tr>
<td>topic_error_code</td><td>The error code for the given topic.</td></tr>
<tr>
<td>topic</td><td>The name of the topic</td></tr>
<tr>
<td>partition_metadata</td><td>Metadata for each partition of the topic.</td></tr>
<tr>
<td>partition_error_code</td><td>The error code for the partition, if any.</td></tr>
<tr>
<td>partition_id</td><td>The id of the partition.</td></tr>
<tr>
<td>leader</td><td>The id of the broker acting as leader for this partition.</td></tr>
<tr>
<td>replicas</td><td>The set of all nodes that host this partition.</td></tr>
<tr>
<td>isr</td><td>The set of nodes that are in sync with the leader for this partition.</td></tr>
</table>
</p>
<h4>LeaderAndIsr API (Key: 4):</h4>

<b>Requests:</b><br>
<p><pre>LeaderAndIsr Request (Version: 0) => controller_id controller_epoch [partition_states] [live_leaders] 
  partition_states => topic partition controller_epoch leader leader_epoch [isr] zk_version [replicas] 
    topic => STRING
    partition => INT32
    controller_epoch => INT32
    leader => INT32
    leader_epoch => INT32
    zk_version => INT32
  live_leaders => id host port 
    id => INT32
    host => STRING
    port => INT32
  controller_id => INT32
  controller_epoch => INT32
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>controller_id</td><td>The controller id.</td></tr>
<tr>
<td>controller_epoch</td><td>The controller epoch.</td></tr>
<tr>
<td>partition_states</td><td></td></tr>
<tr>
<td>topic</td><td>Topic name.</td></tr>
<tr>
<td>partition</td><td>Topic partition id.</td></tr>
<tr>
<td>controller_epoch</td><td>The controller epoch.</td></tr>
<tr>
<td>leader</td><td>The broker id for the leader.</td></tr>
<tr>
<td>leader_epoch</td><td>The leader epoch.</td></tr>
<tr>
<td>isr</td><td>The in sync replica ids.</td></tr>
<tr>
<td>zk_version</td><td>The ZK version.</td></tr>
<tr>
<td>replicas</td><td>The replica ids.</td></tr>
<tr>
<td>live_leaders</td><td></td></tr>
<tr>
<td>id</td><td>The broker id.</td></tr>
<tr>
<td>host</td><td>The hostname of the broker.</td></tr>
<tr>
<td>port</td><td>The port on which the broker accepts requests.</td></tr>
</table>
</p>
<b>Responses:</b><br>
<p><pre>LeaderAndIsr Response (Version: 0) => error_code [partitions] 
  partitions => topic partition error_code 
    topic => STRING
    partition => INT32
    error_code => INT16
  error_code => INT16
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>error_code</td><td>Error code.</td></tr>
<tr>
<td>partitions</td><td></td></tr>
<tr>
<td>topic</td><td>Topic name.</td></tr>
<tr>
<td>partition</td><td>Topic partition id.</td></tr>
<tr>
<td>error_code</td><td>Error code.</td></tr>
</table>
</p>
<h4>StopReplica API (Key: 5):</h4>

<b>Requests:</b><br>
<p><pre>StopReplica Request (Version: 0) => controller_id controller_epoch delete_partitions [partitions] 
  partitions => topic partition 
    topic => STRING
    partition => INT32
  controller_id => INT32
  controller_epoch => INT32
  delete_partitions => INT8
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>controller_id</td><td>The controller id.</td></tr>
<tr>
<td>controller_epoch</td><td>The controller epoch.</td></tr>
<tr>
<td>delete_partitions</td><td>Boolean which indicates if replica's partitions must be deleted.</td></tr>
<tr>
<td>partitions</td><td></td></tr>
<tr>
<td>topic</td><td>Topic name.</td></tr>
<tr>
<td>partition</td><td>Topic partition id.</td></tr>
</table>
</p>
<b>Responses:</b><br>
<p><pre>StopReplica Response (Version: 0) => error_code [partitions] 
  partitions => topic partition error_code 
    topic => STRING
    partition => INT32
    error_code => INT16
  error_code => INT16
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>error_code</td><td>Error code.</td></tr>
<tr>
<td>partitions</td><td></td></tr>
<tr>
<td>topic</td><td>Topic name.</td></tr>
<tr>
<td>partition</td><td>Topic partition id.</td></tr>
<tr>
<td>error_code</td><td>Error code.</td></tr>
</table>
</p>
<h4>UpdateMetadata API (Key: 6):</h4>

<b>Requests:</b><br>
<p><pre>UpdateMetadata Request (Version: 0) => controller_id controller_epoch [partition_states] [live_brokers] 
  partition_states => topic partition controller_epoch leader leader_epoch [isr] zk_version [replicas] 
    topic => STRING
    partition => INT32
    controller_epoch => INT32
    leader => INT32
    leader_epoch => INT32
    zk_version => INT32
  live_brokers => id host port 
    id => INT32
    host => STRING
    port => INT32
  controller_id => INT32
  controller_epoch => INT32
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>controller_id</td><td>The controller id.</td></tr>
<tr>
<td>controller_epoch</td><td>The controller epoch.</td></tr>
<tr>
<td>partition_states</td><td></td></tr>
<tr>
<td>topic</td><td>Topic name.</td></tr>
<tr>
<td>partition</td><td>Topic partition id.</td></tr>
<tr>
<td>controller_epoch</td><td>The controller epoch.</td></tr>
<tr>
<td>leader</td><td>The broker id for the leader.</td></tr>
<tr>
<td>leader_epoch</td><td>The leader epoch.</td></tr>
<tr>
<td>isr</td><td>The in sync replica ids.</td></tr>
<tr>
<td>zk_version</td><td>The ZK version.</td></tr>
<tr>
<td>replicas</td><td>The replica ids.</td></tr>
<tr>
<td>live_brokers</td><td></td></tr>
<tr>
<td>id</td><td>The broker id.</td></tr>
<tr>
<td>host</td><td>The hostname of the broker.</td></tr>
<tr>
<td>port</td><td>The port on which the broker accepts requests.</td></tr>
</table>
</p>
<p><pre>UpdateMetadata Request (Version: 1) => controller_id controller_epoch [partition_states] [live_brokers] 
  partition_states => topic partition controller_epoch leader leader_epoch [isr] zk_version [replicas] 
    topic => STRING
    partition => INT32
    controller_epoch => INT32
    leader => INT32
    leader_epoch => INT32
    zk_version => INT32
  live_brokers => id [end_points] 
    end_points => port host security_protocol_type 
      port => INT32
      host => STRING
      security_protocol_type => INT16
    id => INT32
  controller_id => INT32
  controller_epoch => INT32
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>controller_id</td><td>The controller id.</td></tr>
<tr>
<td>controller_epoch</td><td>The controller epoch.</td></tr>
<tr>
<td>partition_states</td><td></td></tr>
<tr>
<td>topic</td><td>Topic name.</td></tr>
<tr>
<td>partition</td><td>Topic partition id.</td></tr>
<tr>
<td>controller_epoch</td><td>The controller epoch.</td></tr>
<tr>
<td>leader</td><td>The broker id for the leader.</td></tr>
<tr>
<td>leader_epoch</td><td>The leader epoch.</td></tr>
<tr>
<td>isr</td><td>The in sync replica ids.</td></tr>
<tr>
<td>zk_version</td><td>The ZK version.</td></tr>
<tr>
<td>replicas</td><td>The replica ids.</td></tr>
<tr>
<td>live_brokers</td><td></td></tr>
<tr>
<td>id</td><td>The broker id.</td></tr>
<tr>
<td>end_points</td><td></td></tr>
<tr>
<td>port</td><td>The port on which the broker accepts requests.</td></tr>
<tr>
<td>host</td><td>The hostname of the broker.</td></tr>
<tr>
<td>security_protocol_type</td><td>The security protocol type.</td></tr>
</table>
</p>
<b>Responses:</b><br>
<p><pre>UpdateMetadata Response (Version: 0) => error_code 
  error_code => INT16
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>error_code</td><td>Error code.</td></tr>
</table>
</p>
<p><pre>UpdateMetadata Response (Version: 1) => error_code 
  error_code => INT16
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>error_code</td><td>Error code.</td></tr>
</table>
</p>
<h4>ControlledShutdown API (Key: 7):</h4>

<b>Requests:</b><br>
</p>
<p><pre>ControlledShutdown Request (Version: 1) => broker_id 
  broker_id => INT32
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>broker_id</td><td>The id of the broker for which controlled shutdown has been requested.</td></tr>
</table>
</p>
<b>Responses:</b><br>
</p>
<p><pre>ControlledShutdown Response (Version: 1) => error_code [partitions_remaining] 
  partitions_remaining => topic partition 
    topic => STRING
    partition => INT32
  error_code => INT16
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>error_code</td><td></td></tr>
<tr>
<td>partitions_remaining</td><td>The partitions that the broker still leads.</td></tr>
<tr>
<td>topic</td><td></td></tr>
<tr>
<td>partition</td><td>Topic partition id.</td></tr>
</table>
</p>
<h4>OffsetCommit API (Key: 8):</h4>

<b>Requests:</b><br>
<p><pre>OffsetCommit Request (Version: 0) => group_id [topics] 
  topics => topic [partitions] 
    partitions => partition offset metadata 
      partition => INT32
      offset => INT64
      metadata => STRING
    topic => STRING
  group_id => STRING
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>group_id</td><td>The group id.</td></tr>
<tr>
<td>topics</td><td>Topics to commit offsets.</td></tr>
<tr>
<td>topic</td><td>Topic to commit.</td></tr>
<tr>
<td>partitions</td><td>Partitions to commit offsets.</td></tr>
<tr>
<td>partition</td><td>Topic partition id.</td></tr>
<tr>
<td>offset</td><td>Message offset to be committed.</td></tr>
<tr>
<td>metadata</td><td>Any associated metadata the client wants to keep.</td></tr>
</table>
</p>
<p><pre>OffsetCommit Request (Version: 1) => group_id group_generation_id member_id [topics] 
  topics => topic [partitions] 
    partitions => partition offset timestamp metadata 
      partition => INT32
      offset => INT64
      timestamp => INT64
      metadata => STRING
    topic => STRING
  group_id => STRING
  group_generation_id => INT32
  member_id => STRING
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>group_id</td><td>The group id.</td></tr>
<tr>
<td>group_generation_id</td><td>The generation of the group.</td></tr>
<tr>
<td>member_id</td><td>The member id assigned by the group coordinator.</td></tr>
<tr>
<td>topics</td><td>Topics to commit offsets.</td></tr>
<tr>
<td>topic</td><td>Topic to commit.</td></tr>
<tr>
<td>partitions</td><td>Partitions to commit offsets.</td></tr>
<tr>
<td>partition</td><td>Topic partition id.</td></tr>
<tr>
<td>offset</td><td>Message offset to be committed.</td></tr>
<tr>
<td>timestamp</td><td>Timestamp of the commit</td></tr>
<tr>
<td>metadata</td><td>Any associated metadata the client wants to keep.</td></tr>
</table>
</p>
<p><pre>OffsetCommit Request (Version: 2) => group_id group_generation_id member_id retention_time [topics] 
  topics => topic [partitions] 
    partitions => partition offset metadata 
      partition => INT32
      offset => INT64
      metadata => STRING
    topic => STRING
  group_id => STRING
  group_generation_id => INT32
  member_id => STRING
  retention_time => INT64
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>group_id</td><td>The group id.</td></tr>
<tr>
<td>group_generation_id</td><td>The generation of the consumer group.</td></tr>
<tr>
<td>member_id</td><td>The consumer id assigned by the group coordinator.</td></tr>
<tr>
<td>retention_time</td><td>Time period in ms to retain the offset.</td></tr>
<tr>
<td>topics</td><td>Topics to commit offsets.</td></tr>
<tr>
<td>topic</td><td>Topic to commit.</td></tr>
<tr>
<td>partitions</td><td>Partitions to commit offsets.</td></tr>
<tr>
<td>partition</td><td>Topic partition id.</td></tr>
<tr>
<td>offset</td><td>Message offset to be committed.</td></tr>
<tr>
<td>metadata</td><td>Any associated metadata the client wants to keep.</td></tr>
</table>
</p>
<b>Responses:</b><br>
<p><pre>OffsetCommit Response (Version: 0) => [responses] 
  responses => topic [partition_responses] 
    partition_responses => partition error_code 
      partition => INT32
      error_code => INT16
    topic => STRING
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>responses</td><td></td></tr>
<tr>
<td>topic</td><td></td></tr>
<tr>
<td>partition_responses</td><td></td></tr>
<tr>
<td>partition</td><td>Topic partition id.</td></tr>
<tr>
<td>error_code</td><td></td></tr>
</table>
</p>
<p><pre>OffsetCommit Response (Version: 1) => [responses] 
  responses => topic [partition_responses] 
    partition_responses => partition error_code 
      partition => INT32
      error_code => INT16
    topic => STRING
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>responses</td><td></td></tr>
<tr>
<td>topic</td><td></td></tr>
<tr>
<td>partition_responses</td><td></td></tr>
<tr>
<td>partition</td><td>Topic partition id.</td></tr>
<tr>
<td>error_code</td><td></td></tr>
</table>
</p>
<p><pre>OffsetCommit Response (Version: 2) => [responses] 
  responses => topic [partition_responses] 
    partition_responses => partition error_code 
      partition => INT32
      error_code => INT16
    topic => STRING
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>responses</td><td></td></tr>
<tr>
<td>topic</td><td></td></tr>
<tr>
<td>partition_responses</td><td></td></tr>
<tr>
<td>partition</td><td>Topic partition id.</td></tr>
<tr>
<td>error_code</td><td></td></tr>
</table>
</p>
<h4>OffsetFetch API (Key: 9):</h4>

<b>Requests:</b><br>
<p><pre>OffsetFetch Request (Version: 0) => group_id [topics] 
  topics => topic [partitions] 
    partitions => partition 
      partition => INT32
    topic => STRING
  group_id => STRING
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>group_id</td><td>The consumer group id.</td></tr>
<tr>
<td>topics</td><td>Topics to fetch offsets.</td></tr>
<tr>
<td>topic</td><td>Topic to fetch offset.</td></tr>
<tr>
<td>partitions</td><td>Partitions to fetch offsets.</td></tr>
<tr>
<td>partition</td><td>Topic partition id.</td></tr>
</table>
</p>
<p><pre>OffsetFetch Request (Version: 1) => group_id [topics] 
  topics => topic [partitions] 
    partitions => partition 
      partition => INT32
    topic => STRING
  group_id => STRING
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>group_id</td><td>The consumer group id.</td></tr>
<tr>
<td>topics</td><td>Topics to fetch offsets.</td></tr>
<tr>
<td>topic</td><td>Topic to fetch offset.</td></tr>
<tr>
<td>partitions</td><td>Partitions to fetch offsets.</td></tr>
<tr>
<td>partition</td><td>Topic partition id.</td></tr>
</table>
</p>
<b>Responses:</b><br>
<p><pre>OffsetFetch Response (Version: 0) => [responses] 
  responses => topic [partition_responses] 
    partition_responses => partition offset metadata error_code 
      partition => INT32
      offset => INT64
      metadata => STRING
      error_code => INT16
    topic => STRING
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>responses</td><td></td></tr>
<tr>
<td>topic</td><td></td></tr>
<tr>
<td>partition_responses</td><td></td></tr>
<tr>
<td>partition</td><td>Topic partition id.</td></tr>
<tr>
<td>offset</td><td>Last committed message offset.</td></tr>
<tr>
<td>metadata</td><td>Any associated metadata the client wants to keep.</td></tr>
<tr>
<td>error_code</td><td></td></tr>
</table>
</p>
<p><pre>OffsetFetch Response (Version: 1) => [responses] 
  responses => topic [partition_responses] 
    partition_responses => partition offset metadata error_code 
      partition => INT32
      offset => INT64
      metadata => STRING
      error_code => INT16
    topic => STRING
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>responses</td><td></td></tr>
<tr>
<td>topic</td><td></td></tr>
<tr>
<td>partition_responses</td><td></td></tr>
<tr>
<td>partition</td><td>Topic partition id.</td></tr>
<tr>
<td>offset</td><td>Last committed message offset.</td></tr>
<tr>
<td>metadata</td><td>Any associated metadata the client wants to keep.</td></tr>
<tr>
<td>error_code</td><td></td></tr>
</table>
</p>
<h4>GroupCoordinator API (Key: 10):</h4>

<b>Requests:</b><br>
<p><pre>GroupCoordinator Request (Version: 0) => group_id 
  group_id => STRING
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>group_id</td><td>The unique group id.</td></tr>
</table>
</p>
<b>Responses:</b><br>
<p><pre>GroupCoordinator Response (Version: 0) => error_code coordinator 
  coordinator => node_id host port 
    node_id => INT32
    host => STRING
    port => INT32
  error_code => INT16
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>error_code</td><td></td></tr>
<tr>
<td>coordinator</td><td>Host and port information for the coordinator for a consumer group.</td></tr>
<tr>
<td>node_id</td><td>The broker id.</td></tr>
<tr>
<td>host</td><td>The hostname of the broker.</td></tr>
<tr>
<td>port</td><td>The port on which the broker accepts requests.</td></tr>
</table>
</p>
<h4>JoinGroup API (Key: 11):</h4>

<b>Requests:</b><br>
<p><pre>JoinGroup Request (Version: 0) => group_id session_timeout member_id protocol_type [group_protocols] 
  group_protocols => protocol_name protocol_metadata 
    protocol_name => STRING
    protocol_metadata => BYTES
  group_id => STRING
  session_timeout => INT32
  member_id => STRING
  protocol_type => STRING
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>group_id</td><td>The group id.</td></tr>
<tr>
<td>session_timeout</td><td>The coordinator considers the consumer dead if it receives no heartbeat after this timeout in ms.</td></tr>
<tr>
<td>member_id</td><td>The assigned consumer id or an empty string for a new consumer.</td></tr>
<tr>
<td>protocol_type</td><td>Unique name for class of protocols implemented by group</td></tr>
<tr>
<td>group_protocols</td><td>List of protocols that the member supports</td></tr>
<tr>
<td>protocol_name</td><td></td></tr>
<tr>
<td>protocol_metadata</td><td></td></tr>
</table>
</p>
<b>Responses:</b><br>
<p><pre>JoinGroup Response (Version: 0) => error_code generation_id group_protocol leader_id member_id [members] 
  members => member_id member_metadata 
    member_id => STRING
    member_metadata => BYTES
  error_code => INT16
  generation_id => INT32
  group_protocol => STRING
  leader_id => STRING
  member_id => STRING
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>error_code</td><td></td></tr>
<tr>
<td>generation_id</td><td>The generation of the consumer group.</td></tr>
<tr>
<td>group_protocol</td><td>The group protocol selected by the coordinator</td></tr>
<tr>
<td>leader_id</td><td>The leader of the group</td></tr>
<tr>
<td>member_id</td><td>The consumer id assigned by the group coordinator.</td></tr>
<tr>
<td>members</td><td></td></tr>
<tr>
<td>member_id</td><td></td></tr>
<tr>
<td>member_metadata</td><td></td></tr>
</table>
</p>
<h4>Heartbeat API (Key: 12):</h4>

<b>Requests:</b><br>
<p><pre>Heartbeat Request (Version: 0) => group_id group_generation_id member_id 
  group_id => STRING
  group_generation_id => INT32
  member_id => STRING
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>group_id</td><td>The group id.</td></tr>
<tr>
<td>group_generation_id</td><td>The generation of the group.</td></tr>
<tr>
<td>member_id</td><td>The member id assigned by the group coordinator.</td></tr>
</table>
</p>
<b>Responses:</b><br>
<p><pre>Heartbeat Response (Version: 0) => error_code 
  error_code => INT16
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>error_code</td><td></td></tr>
</table>
</p>
<h4>LeaveGroup API (Key: 13):</h4>

<b>Requests:</b><br>
<p><pre>LeaveGroup Request (Version: 0) => group_id member_id 
  group_id => STRING
  member_id => STRING
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>group_id</td><td>The group id.</td></tr>
<tr>
<td>member_id</td><td>The member id assigned by the group coordinator.</td></tr>
</table>
</p>
<b>Responses:</b><br>
<p><pre>LeaveGroup Response (Version: 0) => error_code 
  error_code => INT16
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>error_code</td><td></td></tr>
</table>
</p>
<h4>SyncGroup API (Key: 14):</h4>

<b>Requests:</b><br>
<p><pre>SyncGroup Request (Version: 0) => group_id generation_id member_id [group_assignment] 
  group_assignment => member_id member_assignment 
    member_id => STRING
    member_assignment => BYTES
  group_id => STRING
  generation_id => INT32
  member_id => STRING
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>group_id</td><td></td></tr>
<tr>
<td>generation_id</td><td></td></tr>
<tr>
<td>member_id</td><td></td></tr>
<tr>
<td>group_assignment</td><td></td></tr>
<tr>
<td>member_id</td><td></td></tr>
<tr>
<td>member_assignment</td><td></td></tr>
</table>
</p>
<b>Responses:</b><br>
<p><pre>SyncGroup Response (Version: 0) => error_code member_assignment 
  error_code => INT16
  member_assignment => BYTES
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>error_code</td><td></td></tr>
<tr>
<td>member_assignment</td><td></td></tr>
</table>
</p>
<h4>DescribeGroups API (Key: 15):</h4>

<b>Requests:</b><br>
<p><pre>DescribeGroups Request (Version: 0) => [group_ids] 
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>group_ids</td><td>List of groupIds to request metadata for (an empty groupId array will return empty group metadata).</td></tr>
</table>
</p>
<b>Responses:</b><br>
<p><pre>DescribeGroups Response (Version: 0) => [groups] 
  groups => error_code group_id state protocol_type protocol [members] 
    members => member_id client_id client_host member_metadata member_assignment 
      member_id => STRING
      client_id => STRING
      client_host => STRING
      member_metadata => BYTES
      member_assignment => BYTES
    error_code => INT16
    group_id => STRING
    state => STRING
    protocol_type => STRING
    protocol => STRING
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>groups</td><td></td></tr>
<tr>
<td>error_code</td><td></td></tr>
<tr>
<td>group_id</td><td></td></tr>
<tr>
<td>state</td><td>The current state of the group (one of: Dead, Stable, AwaitingSync, or PreparingRebalance, or empty if there is no active group)</td></tr>
<tr>
<td>protocol_type</td><td>The current group protocol type (will be empty if the there is no active group)</td></tr>
<tr>
<td>protocol</td><td>The current group protocol (only provided if the group is Stable)</td></tr>
<tr>
<td>members</td><td>Current group members (only provided if the group is not Dead)</td></tr>
<tr>
<td>member_id</td><td>The memberId assigned by the coordinator</td></tr>
<tr>
<td>client_id</td><td>The client id used in the member's latest join group request</td></tr>
<tr>
<td>client_host</td><td>The client host used in the request session corresponding to the member's join group.</td></tr>
<tr>
<td>member_metadata</td><td>The metadata corresponding to the current group protocol in use (will only be present if the group is stable).</td></tr>
<tr>
<td>member_assignment</td><td>The current assignment provided by the group leader (will only be present if the group is stable).</td></tr>
</table>
</p>
<h4>ListGroups API (Key: 16):</h4>

<b>Requests:</b><br>
<p><pre>ListGroups Request (Version: 0) => 
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
</table>
</p>
<b>Responses:</b><br>
<p><pre>ListGroups Response (Version: 0) => error_code [groups] 
  groups => group_id protocol_type 
    group_id => STRING
    protocol_type => STRING
  error_code => INT16
</pre><table class="data-table"><tbody>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
<tr>
<td>error_code</td><td></td></tr>
<tr>
<td>groups</td><td></td></tr>
<tr>
<td>group_id</td><td></td></tr>
<tr>
<td>protocol_type</td><td></td></tr>
</table>
</p>